Obi-Wan Kenobi used Form III.
Darth Sidious was also one of the greatest and most skilled Sith swordmasters, as he has mastered all the seven lightsaber forms, all their stances and techniques and is capable of using each form equally effective ambidextrously.
Obi-Wan Kenobi adopts a Form I stance. Form I was the most ancient lightsaber form still in use at the time of the Jedi's fall. In fact, it was the first form created, codifying standard lightsaber techniques in the early centuries of the Jedi Order.
Notable users of this combat form during the Old Republic included Yoda and Qui-Gon Jinn. The New Jedi Order preserved knowledge of Ataru, and Jedi Masters such as Luke Skywalker, Mara Jade Skywalker, and Kyle Katarn all employed it.
Form VI, also known as Niman, was the sixth form of lightsaber combat used by members of the Jedi Order.
Lightsaber. Form VII, known by its two primary disciplines of Juyo and Vaapad; and also known as The Ferocity Form, was the seventh form of lightsaber combat. It was considered the most aggressive and unpredictable form.
Practitioners of Form V included Jedi Masters Aayla Secura, Adi Gallia, Plo Koon and Luke Skywalker, Jedi Knights Anakin Skywalker and Ulic Qel-Droma, and Dark Lord of the Sith Darth Bane.
Form II relied on careful and controlled strikes instead of power and strength. Count Dooku was a master of this form and trained the Sith assassin Asajj Ventress in its use, though hers was less elegant than her master's.
Proficient in its use, Jedi Master Depa Billaba taught her students, including Caleb Dume—who changed his name to Kanan Jarrus after Order 66—to use Form III during close-quarter fighting.
Obi-Wan Kenobi was highly skilled in Form III. Over the course of the Clone Wars, Kenobi continued to develop his skills.
Sokan was a form of lightsaber combat. Developed by the ancient Jedi Knights during the Great Sith War, Sokan combined tactics that allowed for evasion and mobility with the kinetic motions of Form V combat.
The Forbidden Forms were forms of lightsaber combat used by the Sith during the Sith Wars. According to the testimonies of the Jedi Cervil the Uncanny, lightwhips—a lightsaber variant with a flexible blade—were used to defend against Sith Lords who utilized the forms.
Billaba became Windu's Padawan and trained under the Jedi Master in the ways of the Force. During her training, Windu allowed her to study Form VII variant known as Vaapad. She eventually became a Jedi Knight, renowned for her skills with a lightsaber and favored Form III when teaching other Jedi.
N'Kata Del Gormo was a Force-sensitive male Hysalrian Jedi Master who lived during the times of the Galactic Republic. According to legend, he found and trained Yoda and a Force-sensitive Human friend.
Yoda's lightsaber was the weapon carried by Grand Master Yoda. Its blade was shorter than that of a normal lightsaber to match Yoda's small stature, and was green. He used this blade to perfect all styles of lightsaber combat, most notably Form IV: Ataru.
Yoda employs Form IV, which is called Ataru. As seen in his battles throughout the prequels, this particular form relies heavily on aggressive attacks and acrobatics, as well as an emphasis on using the Force to enhance their movements, strikes, and agility.
Form IV, also known as Ataru (pronounced uh-TAR-oo) or The Aggression Form, was the fourth form of lightsaber combat invented by the Jedi Order. An acrobatic combat style, Ataru could be used to defend against incoming projectiles but was best suited for open spaces and attacking.
Other Jedi practitioners of Makashi included Dooku's former Padawan Qui-Gon Jinn; famed Jedi Battlemaster Cin Drallig; Jedi Council Master Shaak Ti; and Master Jerec, who was said to have mastered the form. Grand Master Yoda appeared to have also used the form, as he had once taught Dooku the Makashi salute.
Despite their biologic nature, rainbow gems could be used as lightsaber crystals. Tenel Ka Djo, the Princess of Hapes, had a tiara of rainbow gems worth the price of an entire solar system. She used some of the crystals in her second lightsaber, after her first one malfunctioned and led to the loss of her arm.
At first, Rey primarily fights with a lightsaber the same way she would have with her quarterstaff. However, after studying Luke's Jedi scripture and training with Leia, Rey probably uses Form VI: Niman, a jack-of-all-trades lightsaber form that combines different aspects of Forms I through V.
Irek, his brain devoid of anything but his implant, his instincts, some combat programming, and some deep-level motivations like killing Jedi and taking over Force nexuses, awoke and killed his mother, cutting her into approximately eight pieces with his lightsabers.
Form IX: Kadeesh was a Form of lightsaber combat mainly focusing on the use of brute strength rather than Force-assisted movements or fancy and unpredictable parries.
Form VI, also known as Niman, the Way of the Rancor, the Moderation Form, and the diplomat's form, was the sixth form of the seven forms of lightsaber combat. This fighting style was a hybrid martial art created by effectively combining elements of the preceding lightsaber forms into a single, generalized form.